The present invention generally relates to surface marks on objects and, more particularly, is concerned with a method of objectively evaluating a surface mark. The term xe2x80x9cmarkxe2x80x9d as used hereinafter means any visible trace or impression on a surface, such as a line, dot, spot, stain, scratch, mar, blemish, dent, bruise, etc., on the surface.
A human observer perceives a mark on a surface of an object, such as an automotive body panel, as a point of contrast from the rest of the surface. The contrast seen by the human observer is affected by the size, color and gloss of the mark as well as of the surface that is marked. However, any attempt at visual quantification of the contrast by the human observer will necessarily be subjective and vary from one human observer to the next.
A review of the prior literature and patent art reveals the absence of an objective approach to optical quantification of surface marks. Thus, heretofore the evaluation of surface marks has been mainly dependent upon the subjective perception of the human observer making the evaluation.
Consequently, a need exists for an innovation which will provide an objective approach to quantification of surface marks.
In one embodiment the present invention provides a method of objectively evaluating a surface mark which is designed to satisfy the aforementioned need. Thereto, the method of the present invention provides a reliable objective test methodology for optical quantification of surface marks which avoids the subjectivity of human visual perceptions of surface marks.
In one embodiment the present invention is a method of objectively evaluating a surface mark, comprising the steps of:
reproducibly producing a surface mark on an object; and
optically evaluating the surface mark by optically producing images of the surface mark by (i) illuminating the surface mark at a first angle relative to a reference plane extending substantially perpendicular to the surface mark; and (ii) capturing an image of the illuminated surface mark at a second angle relative to the reference plane, wherein the orientation of the surface mark in the plane of the sample surface is horizontal to image detector means.